<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no">
    <meta http-equiv="X-UA-Compatible" content="ie=edge,chrome=1">
    <meta name="referrer" content="never">
    <title>history</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        ul {
            list-style: none;
        }
    </style>
</head>
<body>
    
    <script type="text/javascript">
        /* 
        history 对象记录了当前标签页用户浏览的过程
            length 总共访问的页面个数
            forward() 前进一页
            back()    后退一页
            go(n)     去往第n个页面，n表示前进/后退数
        */
    </script>
</body>
</html>